Human Factors In Safety: How do stress and fatigue affect work?

What do we mean by human factors, and why are they important?

"Human factors refer to environmental, organisational and job factors, and human and individual characteristics, which influence behaviour at work in a way which can affect health and safety" Health and Safety Executive

Every person is different, meaning that there are as many variables to a job as there are people. Individuals come with a distinct set of skills and personality, therefore requiring personalized support to maximize their capabilities. Ergonomics (the study of the ways in which working conditions can influence the effectiveness of a task being done) looks at both organizational and human aspects that could contribute to job performance. This includes everything from workplace culture to the optimum height of a desk and work equipment.

Workplace culture builds a foreground for safety, wellbeing and performance, which is why ergonomics, or in other words “human factors engineering”, should by no means be excluded from improvement efforts. Feeling safe and staying clear of injuries can immensely contribute towards increased productivity, for example, by reducing the stress levels of the personnel. Moreover, having the right tools and regular breaks during a workday can significantly reduce errors and increase efficiency, thus benefitting not only the individual but also the organization.

As part of a commitment to a safe environment, organizations should be accountable for educating their employees on possible work-influencing factors, such as fatigue and situation awareness, and making sure all necessary means have been exhausted to facilitate an effective run of the workplace. Management must take a proactive stand on this, and listen to not only the numeric indicators, but rather the human characteristics behind the incidents.

In movies and TV, we have seen examples of incidents being caused by human factors. In the TV programme Breaking Bad, a plane crash was caused by a staff member being upset: in season two of the series, Donald Margolis was mourning over his daughter, which led to him giving the wrong instructions to a commercial airplane causing two planes to crash mid-air. A Hollywood example, but an example nonetheless of how human factors can have catastrophic consequences.

Therefore, clear and precise communication, regular retraining of work skills, and spreading awareness on human factors can reduce human errors and make workers more conscious of their surroundings. So, my tough nut to crack for this week includes looking at the role of the human mind and explaining the how and why organizations should consider human factors in the workplace.

Psychology behind our actions

Risk prevention is not limited to reacting to signals; we must also understand the reasons behind our reactions. Digging deeper into the human mind will help us comprehend how we learn and remember, thus allowing safety initiatives to adjust to these processes accordingly. It is extremely useful to understand what happens in our cognition when we absorb new information and observe the environment. Here is my attempt to briefly explain what goes on inside our crazy minds.

Sensation, Perception & Response

Events in our environment are first processed through our senses, which “forward” information to our short term sensory store that can hold new information for up to 1 second at a time. Sensation is not, however, equal to perception (the action that requires the brain to determine the meaning of the sensory signal, the event). The way in which each of us “gives” a meaning to this sensation depends on our personal past experiences. Just imagine the amount of different perceptions 100 people can have on a sole event, when each one brings in a distinct background with differing experiences.

The second step after perception is response. Each individual sees and perceives information differently, and is therefore likely to respond in a different way too. If I earlier urged you to think of all the possible perceptions of an event, then perhaps it might be even more relevant to think of all the likely responses of the personnel. It is possible that there may be no response after perception, but the information is used for learning by using our working memory, from which the information can be further transmitted into our long-term memory.

Working memory vs. Long- term memory

The difference between working memory and long-term memory is that working memory has a limited capacity and merely serves as a short time memory storage for information that will be used promptly. From working memory, it is possible to transfer information into our long-term memory by learning and training.

Not all memories will be remembered, however. In case of interference, which refers to the input of a new piece of information too soon after another, might lead to information being “wiped out”. Interference can also cause the removal of old memory if the new memory is too similar to the old one. One of the more obvious reasons for losing old memory, or not to remember a new one, is our limited capacity to remember. In the workplace, a new piece of information taking over an old one could be a changed security code for a door, for example.

Hence, from initial perception, our mind begins to find a way to respond to the experience. If we think of the human mind in this way we might be able to better understand the reasoning behind our actions in the workplace in order to address those issues. A very relevant example, brought forward by D. Wickens et al., is that of decision-making. We all have to make decisions at work. This requires understanding lot of new information whilst analysing this on the basis of our old knowledge. In other words, we use our memory to fill in the “missing cues” of the situation. However, since our memory is prone to errors, we must be wary of this. It is suggested then that a good decision maker is able to recognize the key information he/she requires to know before they can successfully make the call.

Fatigue & Stress

There are other variables that might affect our ability to fully assess a situation. Let’s think about fatigue and stress. How much information are we actually able to absorb when the clock hits 5pm in the afternoon? Or, how well would you be able to consider all relevant points if given 30 seconds to make a decision? Being a leader involves decision-making, and sometimes that decision can impact hundreds and thousands of lives. When the captain of Titanic decided to put on more speed, he relied on the current statistics and good weather. However, had he used his previous experience and knowledge to fill in the “missing cues” of short visibility and icebergs, the accident might have been prevented altogether. In such a big accident, panic also plays its part. Panic is a state of mind that can easily cloud our judgement when under pressure, which can lead to risky situations if we let emotion override our rational thinking.

Let’s have a look at an example that will help us to comprehend the relevance of what we’ve covered so far. Our example worker, Jim, is a project manager in charge of a construction site. He overlooks 150 people and participates in decision-making on a daily basis. The project is going well, and so far there has been no reported incidents. The personnel have been given the chance to work extra weekend shifts, and some workers are already working their 15th consecutive day. Every morning, Jim checks that each site has all necessary workforce and has a team leader assigned to them. One of the most experienced personnel was given the responsibility to supervise a team that included a new member, who had been called in on the same day to fill in a sick leave. The team leader, who at this point was tired due to long working hours and who was overwhelmed by finance issues at home, forgot to inform the new colleague about a safety switch that had to be turned on before using any of the machinery at the station. Hence, the new colleague wasn’t aware of the correct procedures, and he didn’t turn on the switch. This triggered a risky situation with an overflow of electricity through the circuit that could have led to an employee suffering an electric shock.

Now, when deciding what remediation actions to take, what’s more important than the case itself is the way we look at it: Whose mistake was this? Should the new guy have known that a general safety switch was the norm, or was it the team leader’s responsibility since he was in charge of the new member? I think the issue is more complex. First of all, the fact that Jim allowed his staff to work extra hours without monitoring their wellbeing was a root cause of this incident. The team leader could not have been in his right mind after working for so many days whilst worrying about his personal issues.

It is commonly stated that work should be separated from home and vice versa; however, how do you delete such a thing as financial stress from your mind when it is directly connected with work? Workers should have support in this kind of situation, since every one of us will be a safety risk when too tired or stressed.

Being tired at work is not something that should be taken lightly. EHS Today reported that 40% of US workers suffer from fatigue! Fatigue does not only influence our performance, but also our safety. As I mentioned earlier, tiredness affects our judgement and puts our health at risk. You might have heard of Miwa Sado, the Japanese political reporter, who sadly passed away at the age of just 31 years after having worked 159 extra hours for her last month at work. There have been other fatalities in Japan caused by the very same reason of overwork (this cause of death even has its own name in the local language: “karoshi”). So, what is it that organizations should be doing?(I used Christopher D.Wickens et al.’s book Engineering Psychology & Human Performance to understand the basics of perception and memory)

Workplace responsibilities

Organizations can improve their staff’s skill competency by organizing training so that it goes in line with our cognitive abilities. For example, by teaching one task at a time, without interruptions or other new information input, the workers can better digest and acquire the new information. Also, regular re-training will help maintain the skill level of personnel and keep forgetfulness at bay. Bridget Leathley addressed the issue of skill decay via Health+Safe.... Leathley brings forward the issue of skill decay in high risk industries, and points out that despite training certificates’ expiry date, skill competency can significantly decrease before the set date. Especially when talking about safety certificates, it is a risky business to rely on acquired skills that are put in use only once in a blue moon.

Measuring fatigue and other human factors can be a more challenging task. However, companies can educate their employees about the risks involved in working long hours, and pass on non-technical skills to their employees; situation awareness, communication and decision-making, for example. These tools make workers aware of their importance and enable them to work in a safe and efficient manner. An open work culture on the other hand would contribute to nurture a healthy workplace in which issues such as tiredness or stress could be raised without fear of dismissal or judgement. The staff could also have access to regular consultations with a nurse or a doctor.

Tackling the common issue of fatigue is challenging, not least because its effects can vary from person to person. For those looking for advice, there are guides on how to implement a fatigue management plan. Also, tracking simple statistics such as man hours worked and setting limits on overwork can help to regulate the phenomenon. Tools such as EHS software that integrates with a HR program can be incredibly useful in calculating not only lagging but also leading indicators.

So, although I have mainly focussed on the human and individual characteristics of human factors, aspects such as workplace design should not be forgotten. To support the health and efficiency of staff, tools, work spaces and work stations should be designed ergonomically. Also, noise and general disorganization should be reduced to minimum. Human factors engineering helps organizations to not only minimize human errors and maximize productivity, but also to improve their safety performance. When planning training, it is helpful then to consider our capacity to learn and remember. Understanding the human characteristics involved in each job and nourishing a healthy work culture can surprisingly, in our modern world of quantitative data-overload, be the key to a better performing workplace.

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